Application of Tetrazole-Functionalized Thioethers with Different Spacer Lengths in the Self-Assembly of Polyoxometalate-Based Hybrid Compounds

Abstract

Three metal-organic networks based on Keggin-type polyoxometalates (POMs) have been hydrothermally synthesized by tuning the spacer lengths of bis(tetrazole)-functionalized thioether ligands and structurally characterized: [Cu(4)(bmtm)(4)][SiW(12)O(40)]·2H(2)O (1), [Cu(4)(bmte)(3.5)][SiW(12)O(40)] (2), and [Cu(4)(bmtp)(4)][SiW(12)O(40)] (3) [bmtm = 1,1'-bis(1-methyl-5-mercapto-1,2,3,4-tetrazole)methane, bmte = 1,2-bis(1-methyl-5-mercapto-1,2,3,4-tetrazole)ethane, and bmtp = 1,5-bis(1-methyl-5-mercapto-1,2,3,4-tetrazole)pentane]. The spacer lengths and sulfhydryl of bis(tetrazole)-functionalized thioether ligands play important roles in the final framework formation, as shown by X-ray diffraction analysis. In compound 1, with the connection of a N,S bridge of bmtm, two kinds of binuclear Cu(I) units are formed and linked to construct a one-dimensional (1D) chain. The [SiW(12)O(40)](4-) (SiW(12)) cluster provides four terminal O atoms linking four binuclear units to generate a two-dimensional layer with (8(3))(2)(8(5)·10) topology. In compound 2, centrosymmetric octameric moieties composed of two equivalent tetrameric Cu(I) units are bridged by bmte ligands to form a 1D chain. The SiW(12) clusters show an unusual (2,8)-connected mode to connect with the 1D chain and construct a four-connected three-dimensional (3D) network with 5(3)·6(2)·7 topology. Compound 3 exhibits a rare 3D host framework with a type of large cavity and two types of small windows. The SiW(12) clusters as templates are strongly cemented into the large cavities and completely encircled by small windows. Furthermore, the compound 2 bulk-modified carbon-paste electrode (2-CPE) displays good electrocatalytic activity toward the reduction of nitrite.

A novel polyoxometalate-based metal-organic compound constructed from an unprecedented [Ag8(Hpyttz)4(H2pyttz)2] cluster and an in-situ [VW12O40]3− anion

“…Recently, a remarkable branch in the construction of POMs-based MOCs is the combination of POMs with multinuclear subunits [5][6][7]. In previous reports, many multi-metallic organic subunits have been successfully synthesized, such as {Zn 6 (Zn)L 6 }, {Cu 9 (TBC4) 3 }, and {Ag(DATC) 6 } 8 [8][9][10].…”

A Trinuclear Zr‐Substituted Decanuclear Hetero‐Metal Sandwich Tungstoantimonate: Synthesis, Structure and Properties

“…The electrocatalytic activities of 1 toward the reduction of hydrogen peroxide (H 2 O 2 ) and bromate (BrO 3 – ) were studied in 0.5 mol L –1 Na 2 SO 4 + H 2 SO 4 aqueous solution (pH = 4.9) using a scan rate of 50 mV s –1 . As illustrated in Figure S9a/b, it is easy to find that 1 has moderate electrocatalytic activities towards the reduction of hydrogen peroxide and bromate . According to the method introduced by Keita, the catalytic efficiency is defined as CAT = [ I p (POM, substrate) – I p (POM)]/ I p (POM) × 100 %, where I p (POM, substrate) where I p (POM, substrate) is the reduction current of the POM in the presence of substrate (H 2 O 2 or BrO 3 – ) and the I p (POM) is the current of the POM without the presence of substrate.…”

Metallosupramolecular Compounds Based on Copper(II/I) Chloride and Two Bis-Tetrazole Organosulfur Ligands

“…In the literature there is structural information on several compounds based on copper (II/I ) and these two ligands [11][12][13][14]. These compounds are 1D, 2D or 3D coordination polymers in which the ligands are able to coordinate two, three or four copper cations by chelating and/or bridging coordination modes.…”